Alphabet Inc (NASDAQ:GOOGL) Google autonomous cars boast more driving experience than any human driver has been on the road. The company this week provided an update on the miles its driverless vehicles have logged on public roads since they began road test.

It turns out that Google’s self-driving cars have covered 2 million miles on fully-autonomous mode on public roads. The company further said that 90% of the driving time of its autonomous cars have been spend in city streets, which present a more complex driving experience even for humans.

If you put everything together, Google autonomous cars have so far logged 300 years of human driving experience.

Google autonomous cars came from a crazy research project

Google began serious work on creating vehicles that drive themselves in 2009. According to Dmitri Dolgov who heads self-driving technology at Google, they started out with what appeared to be a crazy science-fiction idea. Now Google can boast one of the most advanced autonomous driving technologies and its breakthrough has inspired many startups to take the cue by attempting to develop similar technology.

Google tests its self-driving technology on its in-house prototype car that looks like a pod and on modified Lexus RX450h SUV. The company’s own prototype car is designed without a steering wheel or pedals like you would find in regular cars. Instead, the pod car uses sensors and software for navigation.

Commercializing the technology

Google feels it has developed it self-driving technology enough that it is almost ripe for commercialization. The company intends to start monetizing the technology in 2020, so it has three more years to perfect it.

Google says that 90% of the work on the self-driving technology was completed within the initial two years of working on the project. But the remaining 10% of the work on the technology has been the most demand because that is where the company has spent much time to get it right.

Google claims to be in its own class

Though many startups and traditional automakers such as Ford Motor Company (NYSE:F) are working their own flavors of autonomous car technology, Google says it doesn’t play in their league. Tesla Motors Inc (NASDAQ:TSLA) says that its electric vehicles have covered more than 130 million miles on highway driving on its semi-autonomous driving software known as Autopilot, but Google says that doesn’t compare with what it has achieved.

“Most of ours have been on city streets and this is a very rich environment compared to driving on freeways,” said Dolgov in reference to competitors like Tesla.

Google autonomous cars could file popular use in ride-sharing services. Alphabet stock eased 0.19% to $801.23 in the last session.